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Stephan

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Ross Ice Shelf
« on: February 17, 2019, 09:04:01 PM »
I just wondered that the largest Antarctic Ice Shelf - the Ross Ice Shelf - does not have its own thread. You can see it constantly growing, almost no cracks at its northern edge, apart from two or three seemingly elder ones. And so it didn't show larger calving events for many years or even decades.
Yesterday the northeasternmost corner of it showed a minor calving, an area of around 10 x 2 km broke off, in an area already full of cracks, see attached picture.
« Last Edit: March 25, 2022, 09:37:52 AM by oren »
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oren

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Re: The Ross Ice Shelf Thread
« Reply #1 on: February 19, 2019, 12:51:07 PM »
ASLR had a combined RIS/FRIS thread.

Gray-Wolf

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Re: The Ross Ice Shelf Thread
« Reply #2 on: February 19, 2019, 01:31:43 PM »
Sorry Oren when I search on that all I get is your post above coming back?

My interest in the cryosphere was piqued with a huge crevice on Ross ( from roosevelt to mid shelf) to the point that I spoke with a few guys down at McMurdo who were ,that season, putting sensors along the length of it to monitor movement there?

https://worldview.earthdata.nasa.gov/?p=antarctic&l=VIIRS_SNPP_CorrectedReflectance_TrueColor(hidden),MODIS_Aqua_CorrectedReflectance_TrueColor(hidden),MODIS_Terra_CorrectedReflectance_TrueColor,Coastlines&t=2019-02-17-T00%3A00%3A00Z&z=3&v=-440576,-1281664,-90880,-1121664

I've watched it for over a decade now so the last couple of years of lower sea ice might be allowing more mechanical strains into the shelf hastening its eventual calve?

Through the noughties we saw warm basal water travelling down from the peninsula after it snuck under the circumpolar current (through valleys on the ocean bed) . this water arrived at Ross up to 5 years ago so impacting the grounding line of the shelf?

How close to the crack is this undercut now?
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Tor Bejnar

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Re: The Ross Ice Shelf Thread
« Reply #3 on: February 19, 2019, 04:21:09 PM »
I believe Oren was referring to the thread called
Hazard Analysis for the FRIS/RIS in the 2012 to 2060 Timeframe
I think using the 'search' tool only looks in the folder you are in. When searching for "RIS" in "Antarctica", it finds "FRIS/RIS", if in "The Ross Ice Shelf Thread", you only find Oren's post.

ASLR had a combined RIS/FRIS thread.
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Re: The Ross Ice Shelf Thread
« Reply #4 on: February 19, 2019, 04:49:15 PM »
I believe Oren was referring to the thread called
Hazard Analysis for the FRIS/RIS in the 2012 to 2060 Timeframe
I think using the 'search' tool only looks in the folder you are in. When searching for "RIS" in "Antarctica", it finds "FRIS/RIS", if in "The Ross Ice Shelf Thread", you only find Oren's post.

ASLR had a combined RIS/FRIS thread.
You can broaden or narrow your search
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FredBear

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Re: The Ross Ice Shelf Thread
« Reply #5 on: February 19, 2019, 04:59:40 PM »
The big Ross calving was Mar.14-17 2000, the Ross "coastline" in EODIS appears to be set in 2011 and the shelf has been growing outwards since then.
Most of the Ross ice shelf is not grounded, so can be melted by any available 'warm' water.
I attach an image from:-

Ice Sheet Stability and Sea-Level Rise

    John B. Anderson*

See all authors and affiliations
Science  30 Mar 2007:
Vol. 315, Issue 5820, pp. 1803-1804
DOI: 10.1126/science.1140766
 "PHOTO CREDIT: BASEMAP FROM GOOGLE EARTH. ORIGINAL IMAGE FROM NASA"
« Last Edit: February 19, 2019, 05:06:37 PM by FredBear »

maga

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Re: The Ross Ice Shelf Thread
« Reply #6 on: February 19, 2019, 10:50:53 PM »
Just a comment to Stephans post above: My impression is that it is a piece of old fast ice that broke off, not a real ice berg. But note as well that the major crack directly below the date has expanded several kilometers to the west this year. However, I still expect the next major calving to occur along the even bigger crack behind within the next few years.

Stephan

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Re: The Ross Ice Shelf Thread
« Reply #7 on: February 21, 2019, 08:38:59 PM »
Looking at the shadow this iceberg produces om the water you may be right. It is probably much thinner than a "real ice berg" deriving from the shelf itself and therefore it is likely just a piece of older fast ice closely joint to the ice shelf.
This takes me to the question about the (average) thickness of the Ross Ice Shelf at its sea front, and whether this thickness (which is obviously stable) has been taken into account when it comes to possible MICI instabilities that demand a keel board of > 90-100 m discussed in other topics of this forum?
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Andreas T

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Re: The Ross Ice Shelf Thread
« Reply #8 on: February 21, 2019, 10:49:57 PM »
Marine Ice Cliff Instability is a process which could affect grounded ice as far as I know. This would mean that a floating ice shelf (like Ross) may be affected by Marine Ice Shelf Instability but not MICI if its edge retreats to thicker parts of the shelf, which at the present is not happening.
I also think it is not the keel (below water) but the height above water (freeboard) which is critical. Iceshelves with a ice thickness of more than 300m are calving as tabular icebergs in Antarctica and in Greenland.

Stephan

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Re: The Ross Ice Shelf Thread
« Reply #9 on: February 22, 2019, 04:37:12 PM »
Thank you for that information.
I meant freeboard and not keel, sorry for having it mixed up.
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Re: The Ross Ice Shelf Thread
« Reply #10 on: June 21, 2019, 02:05:43 PM »
Tidal and Thermal Stresses Drive Seismicity Along a Major Ross Ice Shelf Rift

First published: 23 May 2019 https://doi.org/10.1029/2019GL082842

Abstract
Understanding deformation in ice shelves is necessary to evaluate the response of ice shelves to thinning. We study microseismicity associated with ice shelf deformation using nine broadband seismographs deployed near a rift on the Ross Ice Shelf. From December 2014 to November 2016, we detect 5,948 icequakes generated by rift deformation. Locations were determined for 2,515 events using a least squares grid‐search and double‐difference algorithms. Ocean swell, infragravity waves, and a significant tsunami arrival do not affect seismicity. Instead, seismicity correlates with tidal phase on diurnal time scales and inversely correlates with air temperature on multiday and seasonal time scales. Spatial variability in tidal elevation tilts the ice shelf, and seismicity is concentrated while the shelf slopes downward toward the ice front. During especially cold periods, thermal stress and embrittlement enhance fracture along the rift. We propose that thermal stress and tidally driven gravitational stress produce rift seismicity with peak activity in the winter.

Plain Language Summary
In Antarctica, large bodies of floating ice called ice shelves help prevent ice on land from sliding into the ocean. To predict how Antarctica might respond to climate change, we need to understand how ice shelves interact with the environment, including the atmosphere and the ocean. The largest ice shelf, the Ross Ice Shelf, is over 500,000 km2 in area, making it the largest body of floating ice in the world. In this study, we deployed nine seismographs, the same instruments used to study earthquakes, to monitor vibrations and cracking within the Ross Ice Shelf over a 2‐year period. During that time, the instruments detected nearly 6,000 fracture events along a 120‐km‐long crack in the ice shelf. We compared the timing of the cracking to air temperature data, ocean wave activity, and tides to see whether these factors influenced the crack's behavior. We found that fracture occurs most frequently just after high tide during winter and when the air is very cold. We also found that fracture at the rift is not triggered by ocean waves. This work demonstrates that Antarctic ice shelves are very sensitive to the environment and highlights the need to continue studying them.

https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2019GL082842

bligh

pietkuip

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Re: The Ross Ice Shelf Thread
« Reply #11 on: June 22, 2019, 03:57:40 PM »
The Ross ice shelf melting ten times faster than previously thought, according to Nina Kirchner in an item on Swedish television: https://www.svt.se/nyheter/vetenskap/varldens-storsta-flytande-glaciar-smalter-10-ganger-snabbare-an-man-trott

From the abstract of the linked article (available in fulltext):
"We show that basal melt rates beneath a thin and structurally important part of the shelf are an order of magnitude higher than the shelf-wide average. This melting is strongly influenced by a seasonal inflow of solar-heated surface water from the adjacent Ross Sea Polynya that downwells into the ice shelf cavity, nearly tripling basal melt rates during summer. Melting driven by this frequently overlooked process is expected to increase with predicted surface warming."


solartim27

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Re: The Ross Ice Shelf Thread
« Reply #12 on: July 23, 2019, 04:32:20 PM »
Interesting article showing that the Ross melting is from local effects, mostly solar.  Good description of the equipment used.

Quote
The Rosetta scientists took a new approach to gather data from the Ross Sea. They deployed six profiling floats called Air-Launched Autonomous Micro Observer, or ALAMO, floats. They fastened parachutes to the floats and launched them out of a New York Air National Guard airplane from 2,500 feet above the icy waters below. The instruments were programmed to avoid sea ice that could damage their external sensors and antennae. In addition, the team took a novel approach by "parking" the floats on the sea floor between profiling so as to limit their drifting on ocean currents.
https://phys.org/news/2019-07-robots-roaming-antarctic-reveal-ross.amp

Quote
More information: David F. Porter et al, Evolution of the Seasonal Surface Mixed Layer of the Ross Sea, Antarctica, Observed With Autonomous Profiling Floats, Journal of Geophysical Research: Oceans (2019). DOI: 10.1029/2018JC014683
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bligh8

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Re: The Ross Ice Shelf Thread
« Reply #13 on: August 02, 2019, 06:05:53 PM »
https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2019GL084123

Ross Ice Shelf Icequakes Associated with Ocean Gravity Wave Activity


Z. Chen P.D. Bromirski P. Gerstoft R.A. Stephen W.S. Lee S. Yun S.D. Olinger R.C. Aster
D.A. Wiens A.A. Nyblade
First published: 01 August 2019
https://doi.org/10.1029/2019GL084123


Abstract

Gravity waves impacting ice shelves illicit a suite of responses that can affect ice shelf integrity. Broadband seismometers deployed on the Ross Ice Shelf (RIS), complemented by a near‐icefront seafloor hydrophone, establish the association of strong icequake activity with ocean gravity wave amplitudes (AG) below 0.04 Hz. The RIS‐front seismic vertical displacement amplitudes (ASV) are well‐correlated with AG, allowing estimating the frequency‐dependent transfer function from gravity wave amplitude to icefront vertical displacement amplitude (TGSV (f)). TGSV (f) is 0.6‐0.7 at 0.001‐0.01 Hz, but decreases rapidly at higher frequencies. Seismicity of strong icequakes exhibits spatial and seasonal associations with different gravity wave frequency bands, with the strongest icequakes observed at the icefront primarily during the austral summer when sea ice is minimal and swell impacts are strongest.

see also..pdf.. open access...Annals of Glaciology 53(60) 2012  doi: 10.3189/2012AoG60A058
Response of the Ross Ice Shelf, Antarctica, to oceangravity-wave forcing
This is a much more complete paper with lotsof purty images and graphs.

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maga

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Re: The Ross Ice Shelf Thread
« Reply #14 on: September 25, 2019, 09:21:51 PM »
New and very important crack on the east side - expect major calving relatively soon!

Stephan

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Re: The Ross Ice Shelf Thread
« Reply #15 on: November 26, 2019, 10:09:23 PM »
I see Ross Ice Shelf slowly but constantly growing. Some big cracks are ages old and they do not appear to me to be a source of a soon-to-come calving event. So here comes my maybe stupid question: How long has it been since Ross Ice Shelf underwent a major calving?
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Re: The Ross Ice Shelf Thread
« Reply #16 on: November 27, 2019, 01:13:15 AM »
The big one (B15) was after 14 March 2000! (From   arctic.io.  ). Splitting off by 17.03.2000.

Gray-Wolf

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Re: The Ross Ice Shelf Thread
« Reply #17 on: January 24, 2022, 01:46:46 PM »
New and very important crack on the east side - expect major calving relatively soon!

I'd been watching those cracks (& talking with McMurdo about them since the early noughties!

There is a huge crevice behind where B 15 calved 9half way from 'Roosevelt island' (?) to McMurdo

In the late noughties they deployed sensors the whole length of the crack to keep an eye on things but nothing since?

Ross was the one I always worried about?

The ice streams feeding it appear to have crunched to a halt as the Shelf grw in size (rucked/folded strata in the middle of the shelf where ice stalled & more ice over-ran the 'stalled ice'?

The 'back pressure' from those ice steams must be huge!? take enough of the grounding away & I reckon Ross goes real fast
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FredBear

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Re: Ross Ice Shelf
« Reply #18 on: January 02, 2023, 11:51:51 PM »
Quote: There is a huge crevice behind where B 15 calved half way from 'Roosevelt island' (?) to McMurdo
This crevice has just lost some of the annual snow filling by yesterday, the freeze-up around Roosevelt Island has started breaking up and fast ice that had built up to the north-east side of the bay has suddenly turned to mush just when nothing much seemed to be happening. The sun has struck as usual in summer - but one day it will cause more damage to the scene    .    .    .

Often Distant

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Re: Ross Ice Shelf
« Reply #19 on: August 23, 2023, 05:38:09 AM »
A detaching iceberg is dwarfed.

It appears the Ross Ice Shelf may have been cracking for years like a windscreen on the way to shattering. It has not been visible on Worldview. The gif is very rough, but it shows it isn't an artifact. This is very close to McMurdo Station and Scott Base.

After further inquiring, the lines are most likely traverse trails rather than cracks extending south. Planes land on the ice in the bay near the stations.

The orientation on the blue Polar View image is the opposite way around to other images.

« Last Edit: August 23, 2023, 06:13:39 AM by Often Distant »
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Re: Ross Ice Shelf
« Reply #20 on: August 23, 2023, 07:03:52 AM »

Often Distant

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Re: Ross Ice Shelf
« Reply #21 on: August 24, 2023, 01:15:37 AM »
A lot of what appear to be cracks in the images are ice roads. Even across the sea ice when it is fast.

A nearby calving has been approaching for some years though.

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Re: Ross Ice Shelf
« Reply #22 on: August 24, 2023, 06:50:24 AM »
Way around the other side of the ice shelf past Roosevelt Island. Compression tension on the cork.
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Re: Ross Ice Shelf
« Reply #23 on: October 06, 2023, 07:44:00 AM »
With further analysis, I still feel like the Ross Ice Shelf appears massively vulnerable to crumbling apart at the western section. I attach a few gifs though they don't contain much clarity of detail.

The first gif is Sentinel 2 L1C data from 2016 to 2023. It is not a long time range, though it does show the Koettlitz Glacier tongue conglomerate and surrounding ice advancing north slowly from the lower left. The deep southernmost ice rises hundreds of metres thick, with a steep gradient decline to single digit elevation near Brown Island where it is largely constrained, with a narrow escape route to the left of blocking islands. The northward push from Koettlitz is seen pressing forward into the moraine tongue segment, which appears to compromise the stability of the dark ice, somewhat like a thick upright paperback being slightly compressed inward toward the spine. The frontal ice shelf is coloured dark with seabed moraine fossils that also colour the scattered volcanic land masses which seem previously to have been largely connected, uplifted, shunted around and eroded by the forces of the ice shelf, after the forces of seismic activity. Ancient seabed moraine fossils could have been forced west and north through the expanding Ross ice shelf into and over the mountains in an ancient era in which the ice shelf had much more height, volume and thrust. The direction of ice flow in relation to land masses was rerouted with each significant lowering in shelf altitude over the centuries as ice was forced to flow around what it could no longer flow over the top of. The dot formations seen in the dark ice lining out across from Brown Island to meet the Daily Islands upper mid central, indicate previous flow direction and could also indicate area of rock formation underneath the ice such as potential future extension of the islands, or a grounding formation extending straight across adjoining Black Island somewhat like a shallow version of Minna Bluff off Discovery Island, seen cropped to the right of center down the bottom of the gif. If not, they may just indicate shapes of future icebergs rich in sediment destined to float away to open escape route for Koettlitz ice.

The main Ross Ice Shelf to the east beyond White Island and Ross Island, still has an elevation hundreds of metres thick. Though not visible on the gifs, a clear sheer zone between segments is widening as the northward flow of the main pack outpaces westward flow momentum into the McMurdo Ice Shelf section. Western flow seems more of a gravity slide pulling away instead of a strong weighted push which it seems to have lost. Southward flow pushes against it from Ross Island glaciers though there doesn't seem as much feeding into them from the island as the used to be. The Mc Murdo Ice Shelf has thinned past a point where the dark section of the ice shelf lost most of what was feeding into it from the east and from the south. It seems most icebergs from the shelf are unlikely to be very big due to prolonged multi directional crush.  50 years ago ice still seemed to flow north through between Brown Island and Black Island, which seems to have stalled. At some stage in time, ice flow between Black Island and White Island also seems to have stopped feeding into the deep corner segment of the Mc Murdo Ice Shelf. In its place, melt waters flow across growing crevasses of separating ice out to sea.

The second gif is of Nasa Worldview images from 2000 to 2023. Though the resolution is low, it still feels ominous. I tried to find cloudless imagery during heights of melting seasons. The dates vary wildly as the seasons vary wildly. Of note, the region looks largely like it looked at the end of the melt season 8 months ago, as if winter barely even occurred. With last year sea ice melt being ahead of average by about a month, leading up to the record low minimum, which led into freeze being about a month behind average, leading to record low maximum and again well ahead in melt progress, summer in this spot really looks like it has quite a few months of extra bite to it this time. The third gif is of similar imagery, though the focus was on finding dates near minimal fast sea ice at the terminus. Consistent sharp cuts through the sea ice are not a natural phenomena, but are shipping routes to the bases on the southern edge of Hut Point Peninsula on Ross Island.

It seems there is more information of shelf momentum and future ice berg shape outlines captured on high res Polarview still imagery. To better illustrate my reasons for concern, I attach a low res rough study of potential areas of interest worth monitoring. I'm not a scientist. Arrows point rough directions of potential forces that may be in play, as well as point to areas where I feel cracks may be visible. Red x's indicated where ice feed into the frontal shelf from behind have dwindled. I recommend scientists with access to high resolution comparison data of the ice shelf closely survey any active changes in dynamic.

I feel a minor calving may trigger a massive situation and it may be best to relocate away from there. I feel it should be closely monitored, though not from close. It's not like how it was.
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Re: Ross Ice Shelf
« Reply #24 on: October 06, 2023, 03:03:48 PM »
With further analysis, I still feel like the Ross Ice Shelf appears massively vulnerable to crumbling apart at the western section. I attach a few gifs though they don't contain much clarity of detail.

I dunno, I feel like this must be one of the most closely monitored sections of ice in Antarctica due to the research station there. Surely if the glacier was in danger of collapsing in this area, they would see warning signs well in advance and it would be big news.

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Re: Ross Ice Shelf
« Reply #25 on: October 07, 2023, 12:58:31 PM »
I don't know but I see warning signs, though they don't seem well in advance. I attach a couple more Sentinel-1 gifs of events in progress. The first gif shows a lot of activity happening to the shelf ice at Ross Island in recent months. Appears a tension squeeze releasing grip and slipping. Pressure directions look on the verge of shifting in a developing situation. There will be significant calving, and there will be more. The floating ice on the pivot point to the island is under immense load and has potential to soon open up for the ocean to enter in from the east to the Mc Murdo Ice Shelf, or perhaps instead even open in avalanches of ice from the east that could be hundreds of metres high and shift the Earth somewhat in a burst. Hope not. The islands are tiny compared to the volume of ice in the shelf.

In the second gif further south, the ice load bending around White Island also seems to be buckling under increasing strain with cracks seeming to continue extending eastward at varying angles from the northern tip in toward the main pack across through the angled traverse tracks. An expanding amount of ice area appears visibly crushed as if being turned back into snow instead of into icebergs. The tiny island at the top left of the gif simply seems to hold back most of the strain of the whole catchment region and its grip looks extremely fragile. Surely the sector is in danger of collapsing in. I feel the research stations are imperiled.
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Re: Ross Ice Shelf
« Reply #26 on: October 09, 2023, 11:39:57 PM »
Despite the research stations, the region is one of the least monitored and most understudied in the world due to most of the ice shelf being so far south where data capture is sparse. It is not well understood.

I attach another gif further south, of the ice at the point of Minna Bluff in the last couple of years. It looks dramatic. It seems near tipping point. A critical altitude relevant to islands? Fissures are spreading deeper south, with angles appearing perpendicular. A pivotal change in flow dynamics of the incoming shelf is underway that can undermine the stability of the land masses. The reducing size of resulting iceberg formations bending around past the tip out toward White Island indicate a prolonged weakening input into the ice shelf from western most glaciers such as Skelton and perhaps also Mulock and Darwin. The resulting inner ice berg formations have gotten smaller with diminishing strength input, while what could be the main tongue section of Byrd Glacier, could be getting shunting away or could be veering further in to the left to occupy the route. Could it divert so far that a significant portion points directly into the bluff? Will the overpowered glaciers continue flowing into the contained space behind the bluff? Are large bergs making their way around past the tip, destined to be pressed through behind over rock formation into the section between White Island and Minna Bluff? Could land masses be further pushed and flipped around to raise more deep moraines, or open lava portals?

I also add another gif of the northern section zoomed out comparing an early October date each year across 4. The situation at the point of Ross Island is tense. Most of the large inner think shelf tongue which could be Byrd, is actually pointing in toward the island near entirely, partially squeezed toward the visible tension point.
« Last Edit: October 10, 2023, 05:51:53 AM by Often Distant »
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Re: Ross Ice Shelf
« Reply #27 on: October 11, 2023, 09:52:24 PM »
I attach some gifs focusing on the far eastern Roosevelt Island sector. I feel like the next small calving at this point could trigger a massive situation that could shatter through the Ross Ice Shelf, which seems spring loaded against slipping pinning points. There doesn't seem much holding it all together. The cork is about to pop. I'm not sure if those glaciers on the east have names, but I am sure their velocity will soon increase.

I feel that the best case scenario may be that the Ross Ice Shelf has thinned from below enough that it soon calves apart and the pieces float away, releasing tension on far western volcanic land masses. If much of the shelf is to collapse down rather than calve up, tsunami threat is very real. Seas are coming up at any rate.
« Last Edit: October 11, 2023, 11:10:54 PM by Often Distant »
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oren

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Re: Ross Ice Shelf
« Reply #28 on: October 12, 2023, 07:28:14 AM »
As the representative of the amateurs, I am adding an overview map and a couple of locator maps of the Ross ice shelf, to help locate OD's excellent animations and put them in perspective. I am much more familiar with the geography of the PIG/Thwaites region tanks to the many posts on the subject, but am clueless about the Ross sector.






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Re: Ross Ice Shelf
« Reply #29 on: October 14, 2023, 12:11:40 AM »
It seems it may be the old tongue of Skelton that is disintegrating because it drained such a high altitude basin where inflow isn't there for it anymore. The tongue segment may have had to flow through the shelf for hundreds of years after losing the inlet flow.

Byrd Glacier seems to be the one forcing passage through closer to the eastern side of Ross Island, forcing what may be the tongue of Mulock Glacier in toward Ross Island and in toward what I expect are the collapsing Skelton remnants. I guess that the ice at the northern terminus of the ice shelf at the point of Ross Island, has traveled beyond a couple of hundred years to reach the calving front. Ice more central within the shelf between Ross Island and Roosevelt Island could be roughly double that age as it will have traveled roughly twice as far having come from deeper glaciers south east. Between Mulock and Byrd would be a narrow strip of ice originating from Darwin Glacier, which would have also had low feed and speed input so to lack a defined tongue along the length. The iceberg formations at the front of the shelf off Ross Island seem to be cutting across through this segment in toward what may be Byrd flowing up through the middle of the gif.

Between the ice compacting into the McMurdo segment to the left and the ice flowing north on the right, is the growing velocity transition margin separating the two which extends along the bending axis of potential Skelton flow. Inner deep shelf pressure longs to push west. Byrd along with glaciers to the left, is thought to be draining ice from East Antarctica, with the glaciers further right draining West Antarctica.

It seems seas can rise quickly depending on how developing events at this location occur. Spiraling pressure can shake the Earth to the core.
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Re: Ross Ice Shelf
« Reply #30 on: October 14, 2023, 09:37:13 AM »
Agreed, Byrd is one to watch.

sidd

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Re: Ross Ice Shelf
« Reply #31 on: October 25, 2023, 05:11:39 AM »
A few gifs with worldview images. The first couple are direct comparisons between October 18 2000 and October 14 2023 of Byrd at entrance into Ross Ice Shelf. Corrected Reflectance Bands 367 and 721.

The third gif focuses on weather conditions and the northern calving margin against Ross Island, with various dates across 2000-2001, before switching to 2022-2023. A 21 year gap.

The forth one zooms out to focus more on weather conditions, for clues it can provide as to the shape and state of the ice it somewhat molds. A couple of days from early 2000, then recent weeks.
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Re: Ross Ice Shelf
« Reply #32 on: October 25, 2023, 08:23:30 AM »
An update on the calving situation at the point of Ross Island. It looks like a lot of ice will push forward from behind when the top pops off. It looks like the top is popping off.
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